The world leader in the civilian drones sector is switching its focus from leisure photography to more professional uses for its unmanned aerial vehicles, and it sees agriculture as the future for the burgeoning industry.

DJI's campus lies within the High Tech Park of the southern city of Shenzhen, China's Silicon Valley, where visitors are treated to a showroom featuring an array of drones.

Half the space of the showroom is dedicated to the recreational machines like the Phantom series, while the other half shows off the "enterprise" drones for agriculture, public safety, professional photography or film-making.

Piloted from a distance, one drone can cover the same surface as around 30 people and it does the job more efficiently, said Jiang Sanchun, manager of a small company that operates pesticide drones for farmers in northern China.

"Within five years, we went from drones that only took photos to machines specialised in first aid or agriculture," DJI vice president Paul Xu told AFP at the company's headquarters in Shenzhen.

Fighting fires -

DJI was founded in 2006 in an apartment in Shenzhen by Frank Wang, a young graduate with a passion for model planes.

"A drone can monitor energy networks in hard to reach areas or support public security missions," Xu said.

Chinese police use thermal cameras to track down fugitives. In Brazil and California, firefighters use them to get a complete, bird's eye view of a blaze. Zoom lenses can help authorities locate people in rescue missions in remote areas.

"DJI is entering these enterprise markets because that is where their customer base takes them," said Susan Eustis, president of US-based firm WinterGreen Research.

Worldwide drone sales soared by 60 percent last year, according to the Gartner consulting company. Sales are expected to reach $6 billion this year and nearly double to 11.2 billion by 2020.